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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Lindzen, a Professor of Meteorology at the Massachusetts Institute of Technology, was speaking at the House of Commons in a meeting chaired by Christopher Monckton. While the authors of the critique could agree with Lindzen on some grounds, they also found some pretty glaring inaccuracies in his talk.

Lindzen has published a large body of peer-reviewed work on climate change, but his work remains disputed. It's very popular with the skeptic end of the media and he is also member of the academic advisory council to Lord Lawson's Global Warming Policy Foundation.

Points of agreement

The critique starts with the key points on which Lindzen and the UK experts agree. They welcome Lindzen's acceptance of some well established 'knowns' of climate science, including:

"There has been a large increase of atmospheric concentrations of carbon dioxide and other greenhouse gases due to emissions resulting from human activity over the past 150 years [...] Global average surface temperature has very probably warmed by about 0.7°C in the same period [...] Increasing carbon dioxide alone, and in the absence of climate feedbacks, should cause about 1°C warming for each doubling."

"'Uncertain' doesn't imply 'unknown'"

The scientists also agree with Lindzen that scientists should base their arguments on "physical reasoning and data", and that uncertainties should not be exaggerated or ignored - indeed these points are the ground rules by which scientists operate.

Where they disagree is on Lindzen's inference that scientific uncertainty means scientists are ignorant about some key issues, implying we then don't have to be concerned.

One of Lindzen's favourite arguments seems to be his criticism of our knowledge of cloud feedback processes. Climate models suggest a weak to moderate positive cloud feedback, but there are uncertainties associated with how this will change in the future.

In his speech Lindzen suggests that these uncertainties mean "we don't know if there is a problem". The team of experts disagree, saying:

"[Lindzen] is right to draw attention to uncertainties in climate change feedbacks e.g. associated with clouds. However, it is wrong to infer from this that we know nothing about these feedbacks. Contemporary science suggests unambiguously that there is a substantial risk that these feedbacks will lead to human induced surface temperature change considerably larger than 1 °C in global average this century and beyond."

According to the paper, Lindzen makes similar errors in his discussion on sea level rise, reconstructions of solar activity, and climate sensitivity - how much the world's average temperature would rise from a doubling of carbon dioxide in the atmosphere.

Inconsistencies in Lindzen's arguments

The team also point out some pretty glaring inconsistencies in Lindzen's take on some climate topics, for example:

"There is an interesting dichotomy in [Lindzen]'s line of argument between the implication in the rest of the presentation that the climate is rather insensitive to change, and the observation that, on glacial interglacial scales, even very small changes in energy input led to massive change."

They say Lindzen is "not consistent in his discussion of the accuracy of past temperature data" or of climate models.

And elsewhere, the team say, Lindzen makes claims that are simply wrong:

"[Lindzen] claims that the derived sensitivity of climate to a doubling of CO2 is less than 1°C, based on the assumption that all the observed warming is due to atmospheric greenhouse gases. This claim would be wrong even without this assumption [...] The assumption itself is unjustifiable as it neglects other mechanisms that drive climate change."

Lindzen "does a disservice to the scientific method"

The team sums up Lindzen's presentation, saying:

"A pervasive aspect of [Lindzen]'s presentation was the conflation of uncertainty with ignorance; in his view, because we are uncertain about some aspect, we therefore know nothing about it and any estimate of it is mere guesswork. In this way we believe [he] does a disservice to the scientific method, which seeks to develop understanding in the face of inevitable uncertainties in our knowledge of the world in which we live. The scientific method has served society well for many hundreds of years, and we see no reason to doubt its validity for trying to quantify the risk of climate change and its impacts on society this century."

They go on to point out that Lindzen's arguments are not anywhere near sufficient to discount man-made climate change:

"[...] We reassert that there is a substantial risk of human-induced climate change considerably larger than 1°C in global average this century and beyond. There is nothing in [Lindzen']s talk to cast doubt on the existence of this risk."

Scientists in the service of politics?

At Real Climate, Schmidt points out the value of questioning established norms of climate science:

"[Lindzen] has, in times past, raised interesting critiques of the mainstream science. None of them, however, have stood the test of time - but exploring the issues was useful."

"It is up to policymakers, not scientists, to decide whether governments should take concerted mitigating action to try to reduce [the risk of human-induced warming above 1 degree celsius]. On this we do not comment."

Tim Palmer, one of the scientists who wrote this latest response, told us he felt it was important to respond in this case because Lindzen is "an established atmospheric scientist and hence likely to have some influence". He and the other scientists thought it was important to make it clear to UK policymakers that Lindzen's view that the threat of substantial climate change is minimal runs "completely counter to the view of almost all who work actively in the field."

Comments

It's worth looking at the original post on Carbon Brief (first link in the post, above) where -- before the thread was so abruptly closed on Friday 6th -- no other than 'Monckton of Brenchley' and Luboš Motl had waded in with their sycophantic support of Lindzen. Clearly the number of 'likes' received suggests a substantial drive-by of the those in denial. Help in redressing the balance gratefully received.

I've asked that a note can be added to the original post to direct people across to here if they want to continue the discussion.

It seems Monckton and Lindzen are truly "birds of a feather" as they both misrepresent the entire sensitivity issue, and in a way that is obnoxiously unscientific. Monckton even goes so far as to claim he is an "expert" in this issue, claiming with certainty that the climate sensitivity for a doubling of CO2 from preindustrial levels to be at most 1.1C or so. I wonder if Lindzen even realizes how silly he looks to be associated with Monckton? I wonder if Monckton and Lindzen really understand that the Earth has not yet reached a true Earth system equilibrium point from the current 392 ppm of CO2, meaning of course, that even if we stopped pouring CO2 and other greenhouse gases into the atmosphere today, and could keep things at 392 ppm, that the Earth will continue warming for several more decades at least until the slower Earth system feedbacks such as the cryopshere and biosphere reach some new equilibrium? What this means of course is that no one knows even what the current 392 ppm of CO2 means in terms of global temperature once all slower Earth system feedback have completed, thus, how much more absolutely impossible is it to know what the final equilibrium temperature rise would be at 560 ppm! 3C is certainly a very reasonable estimate based on faster feedbacks, and certainly it could be higher once all Earth system feedbacks have kicked in such as cryosphere (including methane release from permfrost) and biosphere.

As John Russell @1, I was surprised to see the merry band of 'skeptics' bashing in at Carbon Brief to the point where the moderators felt they should close down over Easter when they wouldn't be around to closely police the event.
. Beyond the particular scientific criticism of Lindzen, it was quite shocking to hear Lindzen in his talk seriously misrepresent climate science to an audience supposedly unfamiliar with the subject (it being titled Global Warming: How to approach the science.). The erronious accusation he made against NASA GISS has since been laid off onto somebody else. Yet even ignoring this, the complaints by Hoskins et al described in this post are merely part of it.
. In the talk, Lindzen presents Arctic temperatures for different years, not in sequece but shuffled like a card sharp. He also presents a failed 30-year-old argument about global mean temperatures being like 'reading tea leaves' without properly pointing out the data presented was 30 years out of date (ie before the present warming began to bite).
. He states that such average global temperatures always vary by 0.7 deg C whatever the timescale which is utterly untrue. He compares this variation with the Boston temperature record to suggest that if temperatures vary less than +/-15 deg C it is actually of doubtful scientific relevance! (See the end of the video of the first half of the event to hear him splurge this comment here with the second half here (beware title music).
. The man has truly lost it. MIT should really be thinking how to retire the man a.s.a.p. before the embarassment becomes excessive.

Chris G @3, unfortunately, I think that far too many people would see that as a badge of honour, or that they know something the rest of them don't. This is a problem for more than just climate science, it goes to show just how pervasive magical thinking is for a lot of people.

Of course, this only causes more problems for those of us who understand the science, as it creates a halo of people that (somehow) lend an air of credibility to the claims that they have knowledge that is being suppressed.

And I guess in the end, it circles back to the problem of trying to rationalise someone out of a position they may not have rationalised themselves into in the first place. I don't think much can be done with the likes of Monckton, but people like Lindzen, who should know better, only compound the problem.

Apologies if this is deemed off-topic, however I recently chanced upon this somewhat depressing quotation by Max Planck:

A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather its opponents eventually die, and a new generation grows up that is familiar with it.

Source here. - it would be interesting to know the context of his remarks, although I would guess he was thinking of quantum physics.

Now AGW may not be a particularly new scientific truth, but the quotation does emphasize the difficult of overturning beliefs or assumptions that may have fueled a distinguished career, even amongst scientists. Do we really have to wait until Lindzen, Spencer et al to pass away ?

"There is an interesting dichotomy in [Lindzen]'s line of argument between the implication in the rest of the presentation that the climate is rather insensitive to change, and the observation that, on glacial interglacial scales, even very small changes in energy input led to massive change."

Oversimplified, ignores the differences in feedbacks, see here. The more significant glacial/interglacial changes were not in energy, but in tilt and eccentricity leading to seasonal albedo and weather pattern changes leading to global average temperature changes. The worst case at present is if the CO2 increases lead to less concentrated convection, less meridional flow, less storminess on average, stronger polar jets (more positive AO), etc. That could certainly happen and I cannot credibly dispute models suggesting that. But others have suggested the opposite.

I suspect that in the case of anthropogenic global warming, Planck's quote could be paraphrased thus:

An established but ideologically-unpalatable scientific truth does not triumph by convincing its opponents and making them see the light, but rather its its truth eventually manifests regardless of any human disbelief, and a new generation grows up that is familiar with the truth - and despising the previous generations that were too blinkered to acknowledge the scientific truth and address it in time.

I don't think the biosphere response to the kinds of increases in CO2 that we've seen over the past few hundred years are known in great detail yet. Species migration and habitat changes may create a variety of effects that may be positive or negative feedbacks to the initial warming caused by CO2 increases. Ocean acidification is another potential biosphere related response. My point is that supposed "experts" in climate sensitivity, such as Monckton presents himself as cannot possibly known what the long-term climate sensitivity to any given increase in CO2 will be as they are so complex and varied. We've not yet seen the complete equilibrium response to 392 ppm of CO2, so how can anyone possibly know with the kind of certainty that Monckton parades around with what the 560 ppm will be? Probably the best line of research into coming close to estimating what the long-term response will be is looking at the climate of the mid-Pliocene or even Miocene periods, and in doing so, 3C seems quite a reasonable estimate for a doubling, if not a bit low.

Biosphere response over the long-term must be a positive feedback, at at least in terms of albedo: as climate zones move poleward, they all shrink in area (due to latitude change) except for the equatorial rainforest zone. The shrinking zones include the bright polar zone and the bright subtropical desert zone, while the expanding rainforest is dark.

Taking a cue from the Carbon Brief thread, isn't the term "CAGW" essentially a strawman rather than an actual scientific theory? Has anyone other than a climate skeptic actually used this as a term of art? It gets zero hits on Google Scholar.

Eric #7.
IIRC, Lindzen focuses on albedo changes being more influential than GHC changes, but others have calculated that albedo changes were not nearly enough by themselves. In any case, we are seeing significant albedo changes as a result of GHC induced warming. So from a practical standpoint, positive feedbacks may make it so actual nature of the initial forcing matter little.

John Russell @9 - we'll be publishing a post on the Shakun et al. paper you link later tonight.

keith @13 - I view "CAGW" as the next step for climate denialists who are finally willing to admit the planet is warming and humans are somewhat to blame. The next phase of denial is "sensitivity is low and therefore it won't be bad", and thus they construct this "CAGW" strawman, claiming that anyone who acknowledges that the consequences will indeed be bad is a "CAGW alarmist". It's a goalpost shift.

I think you are very right with regard to the shifting of goalposts and I've already detected it in many quarters. A significant number of fake sceptics are now saying, "of course it's warming and human caused" (and pretending they've always believed that) but then going on to say that their complaint is just with the 'alarmists' who suggest the outcome might be catastrophic.

And of course they do nothing to bring up to speed those in denial who are still back at the 'it's all a hoax' stage.

Chris G, the Lindzen's London Illusions thread doesn't present any comments by Lindzen about albedo. It looks like only the response to Lindzen references albedo, specifically the claim that Lindzen is not accounting for cooling by aerosols. It looks like the argument by Lindzen is simply empirical, that there was not enough warming created by the present CO2 concentration to justify the 3C sensitivity claim.

I may have made an inference that Lindzen has not explicitly stated, but for instance, here is an explanation of his for how heat fluxes between equator and pole can make it so that summers are to warm for snow and winters are too cold (loosely paraphrased). The article talks a lot about snow and ice, and Hadley cell circulation.

Since the phase of water on the surface does not add or subtract energy from the earth system, and neither do convective currents, I infer that he is talking about albedo changes.

As I understand it, the vast majority of the energy coming and going from the earth does so through radiative processes. He does state that changes in flux can change the global temperature (which is a function of energy content), and for that to be the case to the extent that was observed in the glacial-interglacial cycles, there has to be a change in the balance point between radiative energy in, and radiative energy out. Changing albedo is the only way that is apparent to me for the presence or absence of ice and snow to have that effect.

I did not see any mention of water vapor feedback in that paper; so, I do not think he was thinking of that being a GHG forcing or feedback.

That paper is 20 years old; so, he may have changed his mind (or modified his hypothesis), but I was not able to quickly find anything more recent where he described a mechanism by which glacial cycles should coincide with Milankovitch cycles, and not have GHGs play a significant role.

There as another aspect. Energy lost is proportional to the fourth power of the absolute temperature (Stefan-Boltzmann). I suspect that means that a body that has a more equal distribution of temperature looses less energy than a body where the energy is concentrated more in some region. (Imagine a plate with one half several degrees higher than the other half versus a plate with the same heat content uniformly distributed.) So, how the energy is distributed would affect the overall balance point (global temperature). However, he talks about how the winter heat flux between pole and equator is increased during periods of high asymmetry, and I think that means that there is more energy distribution taking place. More energy distribution should lead to less total energy loss. This aspect does not agree with his conclusion; so, I do not think this is what he had in mind for how changes in tilt account for the glacial cycles.

Eric,
Also, Lindzen's conclusion from the empirical results assumes that the oceans, ice sheets, permafrost, methane clathrates, and ecologic zones are already in an equilibrium state with the current radiative imbalance. That seems pretty absurd to me.

I'm not saying that the current measurements are wrong; I am saying his conclusion based on them can only be correct if the all the above conditions are met, and I think it is pretty clear that they are not.

1. It is NOT the level of CO2 that is important, but rather the impact of man made greenhouse gases on climate.

2. Although we are far from the benchmark of doubled CO2, climate forcing is already about 3/4 of what we expect from such a doubling.

3. Even if we attribute all warming over the past century to man made greenhouse gases (which we have no basis for doing), the observed warming is only about 1/3-1/6 of what models project. We are logically led to two possibilities:

1. Our models are greatly overestimating the sensitivity of climate to man made greenhouse gases, or
2. The models are correct, but there is some unknown process that has cancelled most of the warming.
..."

I'm thinking he egregiously overlooked a 3rd possibility, that the system has not yet reached an equilibrium.

Are you sure that his 3/4 forcing and 1/3-1/6 observed warming numbers are actually correct?. Does he "show his work"? I wouldn't trust him to have provided accurate information...

...but I agree with your comment about reaching equilibrium. It's sort of like arguing that the bill of sale says the house cost $500k, but that can't be right because you've only paid $30k on the mortgage since you bought it last year.

We have a proof from icecores in last 800ky, that Lindzen talk about equilibrium sensitivity of 1K max is nonsense.

The CO2 levels have been varying 180-280ppm while temps at the poles have been varying by as much as 10K. Taking into account the polar amplification, the average temps still varied by some 5K.

5K with no more than 60% of CO2 change, in those last 4 inter/glacials. These are reconstructed facts rather than climate models, and suggest the equilibrium sensitivity even higher than that of IPCC models. How come is is now "1K for doubling CO2"? I wander what Lindzen and his supporter can say about that.

Bob,
I make no claim as to the correctness of his numbers, but he is competent with math. I was just looking for his idea of a mechanism where orbital forcings could have an effect that was more than GHG forcings. That paper was what I found. And then I found where he argued against a high CO2 sensitivity and, I believe, coming to the wrong conclusion based an a faulty model. The model, and hence the conclusion derived from it, is wrong whether or not the math is correct.

I doubt that his explanation is correct because I gather that he is invoking albedo effects that result from the orbital mechanics, and there can be a two-way interaction between albedo and CO2 content. The same conditions which lower the albedo can cause melting of permafrost leading to release of CO2 and methane. Increasing GHGs without changing the orbit or tilt can also lower the albedo by reducing the extent and duration of snow and ice cover. Since they interact, it would be tricky to attribute x warming from one and y warming the other. By the time the feedbacks play out, it might not matter. (Kind of like vector math; it all adds up the same.)

I'm thinking that if the interaction between the feedbacks and forcings were low, then he might not be entirely unjustified in claiming different sensitivities.

However, it can be measured that the earth is not currently in equilibrium; more energy is coming in than is leaving. That by itself kills the idea that we have already seen the effects that the current level of CO2 will produce. So, there is a lag, and the existence of a lag mandates the existence of the third possibility that Lindzen tries to avoid.

Bob,
Also, the fact that he sent an apology when he made a misrepresentation indicates to me that he has integrity. (Anyone ever seen an apology from Watts or Monkton?) And, he doesn't deny basic things, like that the greenhouse gas effect exists. I think mostly he has cornered himself into an incorrect model, and is unwilling or unable to walk over the wet paint.

Unfortunately, he's been pushing much the same set of incorrect models since his (quite interesting, but quickly disproven) 2001 "Iris" paper. Which with fairly minor changes has been published yet again (3rd time?) as Lindzen and Choi 2011, in a rather off-topic journal, after being rejected from more on-topic publications.

I'm not seeing any signs of recognizing and learning from past errors...

I think that you and I have different definitions for "integrity". To me, a scientist that accuses other of manipulation of data, without looking closely at the data - and especially, who does it very publicly without attempting to contact the people that produced the data for an explanation - is not acting with integrity.

It is quite conceivable that the apology was sincere. It is also conceivable that it was done in the realization that to not apologize - in view of the seriousness of both the accusation and the error committed by Lindzen - would destroy what credibility he has left, or even cost him money in a lawsuit.

If he would address and correct the many other errors and distortions in the presentation, then I might be more inclined to think he has integrity. Fool me once, shame on you. Fool me twice, shame on me (or is that "you can't fool me twice"?)

Such vitriol, Dick Lindzen was only trying to draw attention to the obvious scientific risks of relying on computer models - GIGO, or perhaps "Assumptions In, Assumptions Out"!
Just one example, sea levels. S J Holgate's 2007 paper represents the most comprehensive empirical measurement of decadal sea-level change rates during the 20th century. Between 1904 and 1953 global sea levels rose by 2.03mm per year, whereas from 1954 to 2003 they rose by only 1.45mm per year, giving an annual mean rate of 1.74mm per year over the 100 years to 2003, or seven inches per century. Importantly, there was no increase in the rate of change over the whole century! Hardly a case for alarm I would suggest.

DouglasM @32, actually, what Lindzen did (among other things) is accuse his colleagues of fraud based on (at best) poorly sourced data which he did not double check. In a more genteel age, such a gaffe would have resulting in his resigning his current paid position in disgrace. In this age where the politics of fossil fuel trumps all sense of ethics, he merely apologizes in terms which accuse the those being apologized to of academic negligence - this time based on no greater evidence than that it would be convenient for Lindzen if it were so.

Those politics, and those guided by it, are certainly an example of the GIGO principle. A case in point is your claim that:

Really, Holgate 2007 in which Holgate examined the records of just nine stations is a more comprehensive survey than Jevrejeva et al, 2008, in which they examined 1,023 stations; or than Church and White, 2008 who tracked at least 350? It becomes apparent that "most comprehensive" is a trade term for you, meaning something like "has conclusions most suitable to my prejudices".

Examining Holgate we find that after 1993 his 7 stations diverge substantially from a 177 station record from a previous study of his. If they had instead tracked the 177 station record, then the highest rate of change in sea level would have been at the end of the 20th century (instead of the 1980's). More significantly, his seven gauge record diverges significantly from the still more comprehensive satellite record of 3.1 mm per year over the period 1993 -2003 (compared to the 3.4 mm per year found by Jevrejeva over the same period).

Clearly his "comprehensive" survey of just nine stations must take precedence over his earlier 177 station record, Church and White's 350 station record, Jevrejeva's 1000 station record, and of course the whole of ocean satellite record for that period - at least, that is, if you join with Lindzen and DouglasM in putting the politics ahead of the science.

Tom, oh no, it's going up 12 inches per century, not 7 inches. Statistical sampling using common and consistent data sources for over one hundred years has a good deal of credibility in establishing trend. If Holgate's observations were supposedly understated for the final ten years, they were likely to be understated by equal order for the preceding 90 years - the trend remains! Some comments by Holgate regarding his paper:

"The point of the journal article was to show that global changes in sea level do not proceed smoothly and that there are periods of higher rates of increase along with periods of lower, or even occasional negative change. The paper also shows that the global average sea level has been rising for more than a century, and continues to rise.
Sea levels that coastal dwellers experience is affected by local land movements. These movements include the recovery of the Earth’s surface from the deforming weight of ice sheets during the last Ice Age, subsidence due to water extraction, earthquakes and regional plate tectonics. These effects are carefully taken into account when we calculate the global and regional sea-level changes, but these effects may add or subtract from the relative sea level experienced at the coast."

Perhaps DouglasM you would like to tell us where you got the idea that "S J Holgate's 2007 paper represents the most comprehensive empirical measurement of decadal sea-level change rates during the 20th century." Perhaps not the most reliable source of information?

Douglas, I am not doubting the Holgate paper's analysis of 9 stations. I am questioning your assessment of it as "the most comprehensive" especially when it is not (as you have been shown). Does "generally recognised and often quoted" really mean "lionised on pseudo-skeptic blogs"? I was asking where you got that assessment of the paper from because your source is clearly wrong and you should know that before trusting that same source for other information.

Also before deciding that data contradicts model for sealevel you should see what the science actually expects sealevel rise to be and rate of acceleration (eg Vermeer & Rahmsdorf. See also the discussion here and note the acceleration when you look at the longer century-level time line.

Scaddenp, don't think Dr Holgate would like to think he was being used by pseudo-sceptic blogs, he's certainly no sceptic. First saw the Holgate results (among others) in a CERN lecture, and it was considered the most comprehensive because the sampling covered the whole 20th century! Don't trust models I'm afraid.

DouglasM @35, Holgate's 9 station reconstruction understates the figures for his 177 station series for the last decade of the twentieth century, but overstates them for the first decade of overlap:

Holgate's 9 station reconstruction also disagrees markedly with both Jevrejeva 2008 and Church 2006 over the period from 1900 to 1920. Holgate shows sea levels rising at near 4 mm per year over most of that period, before dropping to 0 mm per year in 1920. Both Jevrejeva and Church show the sea level rising from 0 mm per year in 1900 to just below 2 mm per year before falling back to below 0 mm per year in 1920.

This comparison, by the way, give the lie to your claim that Holgate is the "most comprehensive because the sampling covered the whole 20th century". Church and White 2006 sampled from Jan 1870 to Dec 2001. Jevrejeva et al, 2008 sampled from 1700 to 2002. Whether considering the number of stations, or the duration sampled, both studies are easily more comprehensive than Holgate 2007. But again, and this appears crucial in your assessment, it gives the result you want and therefore its significance must be overstated so that you can ignore the barrage of results you don't like from other sources.

Turning to your throw away comments. (1) Evidence that sea level rise correlates with increased temperatures (which is very strong) suggests that in the 21st century when global means temperatures are expected to rise from 2 to 5 degrees centigrade, sea levels will rise much faster than they have in the twentieth. Suggesting that mere correlation trumps physics (as your comment does) is simply asinine.

(2) That you first learnt of Holgate at a CERN lecture, unfortunately, does not these days mean you did not hear it from a denier source. And certainly the statement of an unnamed source at CERN does not make Holgate 2007 more comprehensive than other studies with far better sampling over far longer durations. Of course, as always, deniers are quick to appeal to argument by authority whenever the "authority" gives them conclusions that suite their politics.

Funny you should say that. Just the other day I was thinking that denial science is the science of hope. So far, denial scientists have been unable to prove anything more than that they hope that climate sensitivity is low. Spencer, Lindzen and others keep looking for ways to prove it, but failing. They also continue to ignore the preponderance of evidence that says otherwise.

In the end, they can't prove that climate sensitivity is low, so they hope that it is low, and hope some day to be able to prove it.

The same goes for deniers who cry "fraud" or distrust (a) climate scientists (b) models (c) the surface temperature record (d) tree rings and proxy studies or (e) anything else that is inconvenient.

They can't actually prove anything. All they can do is to claim that "method x" is untrustworthy, and so it doesn't prove anything, either.

And, in the end, they are left with the nothing but the hope that they are right.

DouglasM - Indeed, the burden of proof lies with the authors of an hypothesis. In this case, the burden would lie with the author of a paper, or those who interpret it as such, whose conclusions lie contrary to those of the wider science community. Unfortunately for you, the evidence of just nine stations is pretty weak versus hundreds plus a satellite record. Even Holgate says there's no statistical significance in the difference between SLR rates in the early and later part of the century from their data.

A CERN thought - why would a CERN talk be authoritative on sea level or climate science? Sure CERN's probably a great place to hear about particle physics. But would my local zoology department be the place to hear authoritative talks on particle physics? What makes you think a speaker at CERN is authoritative on climate science? They could be, but that probably does not depend upon their presence at CERN. We're still left with why you consider this single paper "most authoritative"?

Well, Holgate is not a Climate Scientist. He is, however, an expert (with relevant Doctorate) in Oceanographic Mean Sea Level research, is fully peer reviewed and, as far as I know, his published work has not been challenged. Sounds pretty authoritative to me! I certainly would not want to fly in a plane that had been built using incomplete & proxy data.

Whatever the merits of Holgate's work, it limitations with respect to other papers using much larger no. of guages has been demonstrated here.

What climate model has been created with proxy data? They obviously can be validated against proxy data for paleoclimate studies but that's not how models are built. You havent answered the question as to what your preferred method for forecasting is, since using all available physics doesnt seem to be your preference. However, I suggest you reply to this on this thread as it is off-topic here.

The New York Times has inexplicably published a cogent and thorough look at the state of AGW 'skepticism' with particular emphasis on Lindzen's 'cloud iris' hypothesis and clouds in general as being the 'last bastion' of uncertainty for 'skeptics' to hang their hat on.

Oddly, I didn't see any egregious errors of fact or ludicrous convolutions in the name of providing 'balance'. It was almost as if they were reporting... news. Accurately.

I've heard stories of such things from the olden days, but it is quite a surprise to see it in the here and now. Are unicorns also real?

Yes, its ironic that an real live example of accurate reporting of the news has me suddenly wondering if maybe there are such things as unicorns and Santa Claus! Gillis has been doing yoeman's work reestablishing what true journalistic balance should be about (as opposed to lazy he said-she said balance). It has become so rare in the mainstream media that seeing it now is just plain disorienting.

If I were to quibble (and it is indeed a quibble) it's that he provides a lot more specifics about Lindzen's arguments than he does for the arguments against reduced climate sensitivity via the Iris effect. The arguments against are cast in a more general light. That can leave the impression that Lindzen's ideas are somehow more coherent and that mainstream scientists are being sourpusses. Nothing could be further from the case.

I love Lindzen's quote near the end.

“If I’m right, we’ll have saved money...If I’m wrong, we’ll know it in 50 years and can do something.”

Of course, if Lindzen was wrong, we wouldn't be able to do anything about because climate sensitivity will be high and the effects will substantial and long lasting. What I think he meant was ...

“If I’m right, we’ll have saved money, but if I’m right , we’ll know it in 50 years and can do something.”

To state it simply, to me its clear that he simply can't imagine a scenario where he is wrong. And people claim mainstream climate scientists are arrogant! As Kerry Emmanuel states at the end, "...it just seems deeply unprofessional and irresponsible to look at this and say, ‘We’re sure it’s not a problem.'"

We'll be doing a post on this NY Times cloud/Lindzen article in the near future. It is a good article and really lays out the problem with listening to "skeptics" like Lindzen. As Stephen @49 notes, it also highlights that Lindzen is unable to consider the true consequences if (when) we learn that he's wrong, if we heed his advice and fail to act in the meantime.